Subclinical Hyper/Hypothyroidism

Question 1

Describe TFT findings in subclinical hyperthyroidism

Answer 1

TSH <01
T3/T4 normal

Question 2

Causes of subclinical hyperthyroidism

Answer 2

multinodular goitre (particularly elderly females)

excessive thyroxine treatment

Question 3

Management of subclinical hyperthyroid

Answer 3

TSH may return to normal independently

treatment option = low-dose antithyroid agent for 6 months in an effort to induce a remission

Question 4

Describe TFT findings in subclinical hypothyroidism

Answer 4

• TSH raised
• T3, T4 normal

Question 5

Why is subclinical hypothyroidism clinically significant?

Answer 5

Risk of progressing to overt hypothyroidism
2-5% per year (higher in men)

Question 6

Management of subclinical hypothyroidism

Answer 6

TSH > 10 on 2 occasions
- offer levothyroxine

TSH 5.5-10 on 2 occasions and ?symptomatic
if < 65 years = 6-month trial of levothyroxine
If >80y = ‘watch and wait’

TSH 5.5-10 and asymptomatic
- repeat TFTs in 6 months